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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The anhydride diapirs and structure of central western Axel Heiberg Island, Canadian Arctic Archipelago.

Hoen, Ernst. L. January 1963 (has links)
On central western Axel Heiberg Island, which lies across the axis of the Sverdrup Basin, there are about forty diapirs composed of Lower Pennsylvanian anhydrite and microfossiliferous limestone. Inclusions of foreign sedimentary rock are extremely scarce. Diabase inclusions of undetermined age and intrusions of Upper Cretaceous age are common. The diapirs can be classified into three main groups, based on the structural setting in which they occur: domical diapirs, anticlinal diapirs and fault diapirs. They do not appear to be underlain by rock salt. The hypothesis that these diapirs originated from a thick gypsum layer which was subsequently dehydrated to anhydrite best explains the available data.
42

The geology of the Neal (Virot) Lake area, west of Wabush Lake, Labrador, with special reference to iron deposits.

Jackson, Garth. D. January 1963 (has links)
The area lies along the "Grenville front" in a heavily glaciated area of southwestern Labrador. About 250 modal analyses and associated optical and X-ray determinations, 17 semiquantitative spectrographic iron-formation analyses, 2 chemical analyses of gabbro and amphibolite, and other analyses are reported on. A granitic basement complex is overlain unconformably by metamorphosed, over lapping, stable, shelf-type rocks of the Labrador Geosyncline such as quartzmica- plagioclase schist, graphitic schist, meta-orthoquartzite, silicate-oxidecarbonate iron-formation, and amphibolite of possible volcanic origin. These rocks were probably folded when the Ungava Fold Belt was formed. Later, the area was profoundly affected by the Grenville orogeny. Basic intrusions were emplaced and amphibolized, and minor granitic intrusions were emplaced later during the same orogeny.
43

Physico-chemical modeling of metamorphic reactions.

Katz, Michael. January 1963 (has links)
In this thesis the possibility of modelling mineral reactions using relatively low-melting point materials is studied. The model materials considered were assumed to be more reactive than the minerals, but behaved similarly under suitably reduced physico-chemical conditions. A review of the literature of the sciences related to geology, especially salt chemistry, glaciology, metallurgy, ceramics and glass technology revealed that many cheap and readily available substances could be used as model materials. The "model structures" of the silicates, the fluoberyllates, were also investigated. Twenty simple physico-chemical modelling experiments concerning crystallization, recrystallization, solution, melting and deformation were performed. These experiments utilized alums, salts, iodine, and inert and reactive markers.
44

The Siluro-Devonian stratigraphy of the Matapedia-Temiscouata area.

Lajoie, Jean. January 1963 (has links)
This thesis discusses correlation of the Silurian and Devonian rocks between the Lake Temiscouata and the Lake Matapedia areas. In certain correlations, two solutions are possible; the writer has proposed those which appear most logical at the present. The area is located in the Northern Appalachian Highlands, between the Matapedia and Temiscouata river valleys. The writer has not mapped this entire area by himself, his main work has been directed in the center part of the area. However, for a better understanding of the correlation of Silurian strata between the two extremities, it became necessary to include work done by other workers in both the Matapedia valley, and Lake Temiscouata valley.
45

The geology of the Singida Kimberlite Pipes, Tanganyika.

Mannard, George. W. January 1963 (has links)
Fifty-four kimberlite pipes and dykes cut Precambrian granite in the Singida region of Tanganyika. The pipes range from 60 to 2500 feet in diameter, and occur in clusters and lines. The lines follow fracture zones. In addition to intrusive kimberlite, the pipes contain massive to stratified kimberlite tuff and sedimentary-tuffaceous beds. Some pipes have jackets of explosion breccia. The Singida pipes represent the upper parts of kimberlite volcanoes. The kimberlite consists mostly of serpentine which has replaced olivine. Magnesian ilmenite, pyrope, dark green diopside and perovskite are characteristic accessory minerals. After consolidation the kimberlite was entirely serpentinized, and partly carbonatized and silicified.
46

Geology of Knob Lake Ridge, Schefferville, Quebec.

Seguin, Maurice. January 1963 (has links)
The Knob Lake Ridge is located near Schefferville townsite, three hundred and seventy miles north of Seven Islands; the Knob Lake Ridge defines the New-Quebec-Newfoundland-Labrador boundary adjacent to the critical ore zone. The Labrador trough represents a structural depression seven hundred miles long and twenty to sixty miles in width running southeast-northwest and extending south from the Payne River situated at the 60° parallel on the western shores of Ungava Bay to the fifty first degree parallel. This trough represents a geosyncline that was partially filled by a succession of sedimentary strata.
47

Subsolidus phase relations in the systems Ag-Sb and Ag-Sb-S.

Somanchi, Sitaramayya. January 1963 (has links)
The phase boundaries as obtained in the Ag-Sb system are as follows: Sb-rich solvus of ε phase at 500, 450, 400 and 350, and 300°C is 18.2, 17.7, 17.75 and 17.7 weight per cent Sb respectively. Ag-rich solvus of ε' phase (dyscrasite) at 500, and 450, 400, 350, 300° C is 22.5 and 22.9 weight per cent Sb respectively. Sb-rich solvus of ε' phase at 500, 450, 400 and 350°C is 27.2 weight per cent Sb and at 300°C is 26.9 weight per cent Sb. No inversion of ε’ to ε” at about 440-449°C was observed. The homogeneity range of pyrargyrite is probably less than 1 weight per cent Sb2S3 at 400° C and in miargyrite less than 0.6 weight percent Sb2S3 at 400°C.
48

Melting phenomena in rocks of the anorthosite suite.

Vincent, John. S. January 1963 (has links)
Anorthosites and their associated rock types have been a subject of controversy for a considerable number of years. Several genetic theories have been suggested to explain the observed field characteristics, but none have been completely accepted by authorities on the subject. Theories on the origin of anorthosite may be classed as magnetic, metasomatic, and anatectic, and all contain useful ideas. Where an aspect of the problem appears to be successfully solved by one genetic theory, another remains embarrassingly unexplained. It is quite possible that a complex series of events is responsible for the formation of the anorthosites and their associated rock types. Kranck (1961) points out that, "The origin of the anorthosites is almost as controversial a subject as the granite problem.”
49

A portable gamma ray spectrometer and its geological applications.

Doig, Ronald. P. January 1964 (has links)
The distribution of both the major and trace elements within a rock body is fundamental to the solution of many geologic problems. In most instances a great many analyses are required to represent this distribution accurately. The cost, in terms of expenditure and time, of ordinary analytical procedures limits the number of samples that can be collected and processed. This often results in an inadequate or even erroneous concept of the distribution of an element. The purpose of this project was to design and construct a portable gamma ray spectrometer capable of measuring, in situ, the radioelement content of rocks, and to demonstrate its use on a variety of geologic problems.
50

Sulphur vapour pressure study of the Cu-S system and effects on solid state transport.

Gaskarth, Joseph. W. January 1964 (has links)
The method of transport, and the emplacement of ores is a problem of great importance to the geologist. If we can improve our understanding of how ore bodies are emplaced, the search for new, and the extension of known deposits will be made very much easier. This thesis is a small contribution towards this end.

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